System and method for onset/offset capture

Abstract

A medical device is utilized to monitor physiological parameters of a patient and capture segments of the monitored physiological parameters. The medical device includes circuitry configured to monitor one or more physiological parameters associated with the patient and an analysis module that includes a buffer and a processor. The buffer stores monitored physiological parameters and the processor analyzes the monitored physiological parameters and triggers capture of segments from the buffer in response to a triggering criteria being satisfied. The analysis module selects a pre-trigger duration based at least in part on the triggering criteria.

The invention claimed is: 
     
       1. A medical device for monitoring physiological parameters of a patient and capturing segments of the monitored physiological parameters, the medical device comprising: circuitry configured to monitor a one or more physiological parameters associated with the patient; and an analysis module that includes a buffer to store monitored physiological parameters and a processor to analyze monitored physiological parameters and trigger capture of segments from the buffer in response to a triggering criteria being satisfied, wherein a size of the segment captured in response to a triggering event depends at least in part on a pre-trigger duration, wherein the analysis module selects the pre-trigger duration based at least in part on the triggering criteria. 
     
     
       2. The medical device  claim 1 , wherein the circuitry is electrocardiogram (ECG) circuitry coupled to one or more electrodes to monitor an ECG signal associated with the patient. 
     
     
       3. The medical device of  claim 2 , wherein the triggering criteria defines a number of beats (X) that must exceed a heart rate threshold out of a total number of beats (Y), wherein the pre-trigger duration is selected based at least in part on the total number of beats (Y). 
     
     
       4. The medical device of  claim 3 , wherein the pre-trigger duration is selected based at least in part on a type of arrhythmia being detected by the triggering criteria. 
     
     
       5. The medical device of  claim 3 , wherein the triggering criteria includes a plurality of triggering criteria, each triggering criteria associated with one of a plurality of types of arrhythmia, and wherein the pre-trigger duration is selected based on a maximum trigger duration associated with the plurality of triggering criteria. 
     
     
       6. The medical device of  claim 5 , wherein the pre-trigger duration is selected based on the maximum total number of beats (Y) value utilized by the plurality of triggering criteria. 
     
     
       7. The medical device of  claim 1 , wherein the triggering criteria includes an onset triggering criteria and an offset triggering criteria, wherein the pre-trigger duration is selected based on the onset triggering criteria and an offset pre-trigger duration is selected at least in part based on the offset triggering criteria. 
     
     
       8. The medical device of  claim 1 , wherein the processor identifies onset of condition resulting in triggering criteria being satisfied and measures a time from onset to the triggering criteria. 
     
     
       9. The medical device of  claim 8 , wherein the measured time from onset to the triggering criteria is stored and subsequently analyzed to determine one or more of severity of the condition, progression of the condition, and efficacy of treatment.